Even as colleges nationwide celebrate commencement season, hundreds of schools are failing to graduate a majority of their students in six years, a report says today.

Nationally, four-year colleges graduated an average of just 53% of entering students within six years, and "rates below 50%, 40% and even 30% are distressingly easy to find," says the report by the American Enterprise Institute, a conservative think tank. It's based on data reported to the Education Department by nearly 1,400 schools about full-time first-time students who entered in fall 2001.

Some findings aren't surprising. Harvard University boasts one of the highest rates, 97%. Southern University at New Orleans, which faced upheaval in 2005 with Hurricane Katrina, reported 8%.

Even so, the report documents a "dramatic variation" even across institutions with comparable admissions standards, which suggests some schools are more effective in educating similar students.

"While student motivation, finances and ability matter greatly when it comes to college completion, the practices of higher education institutions matter, too," says lead author Frederick Hess. When similar colleges have a large gap in graduation rates, "it is fair to ask why," the report says.

Education leaders said the report could be useful. "We can learn from universities who are beating the odds," says Geri Malandra of the American Council on Education.

Examples from the study, which grouped schools by categories in Barron's Profiles of American Colleges:

•Among schools that require only a high school diploma for admission, Walla Walla University and Heritage University, both in Washington state, reported graduation rates of 53% and 17%, respectively.

•Among colleges that require high school grades averaging a B-minus or better, John Carroll University in Cleveland and Chicago State University in Illinois graduated 74% vs. 16%, respectively.

•In the "most competitive" group, Amherst College in Massachusetts and Reed College in Portland, Ore., graduated 96% vs. 76%, respectively.

The data have limits: They don't account for students who transfer, for example. And they should not be used as a sole measure of quality, the report says, because "schools should not be unfairly penalized for maintaining high standards."

But as graduation rates grow increasingly central to discussions about accountability, co-author Mark Schneider says, families ought to be thinking that way, too. "We are emphasizing transparency" and urging students to factor graduation rates into decision-making, he says. "It's one of these little secrets that everybody in the industry knows. We're just trying to highlight it."

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